Diamond sensor will quickly detect infections

Photo: Fotolia

A small sensor that immediately detects - for example in the saliva of the patient - pathogens that cause serious infections may prevent doctors from prescribing antibiotics when it does not make sense. A biosensor based on diamonds has been developed by Polish scientists.

For now, it is not so easy to tell that a sneezing patient who comes to see a doctor with a fever and cough has the flu. Relative certainty is offered only by testing samples (mass or PCR) that are not available to ordinary people. These tests are not only expensive, but in addition take a lot of time - you have to wait several days for the results.

Doctors, unable to immediately determine whether they are dealing with a viral or bacterial infection, sometimes prescribe antibiotics just in case. And in the case of the presence of a virus, such as influenza or rhinovirus, it is completely unnecessary and contributes to the weakening of the body, as well as the development of strains of bacteria resistant to antibiotics.

The situation can be changed by handy biosensors for the detection of individual pathogens - the idea of Polish scientists. Engineers from the Tri-City, Warsaw, Łódź and Wrocław are working on the concept.

The sensor would have the size of a glucose meter. A sample of saliva or secretion from the patient\'s nose would be applied to the disposable tip of the device. After a moment, the sensor would indicate the type of infection. The sensor also works at a very early stage of infection when the symptoms are still unnoticeable. Research related to this has been presented in the prestigious "Scientific Reports" at nature.com.

"The sensor is very specific and sensitive to the pathogens we want to detect. This means that the presence of other microorganisms in the mouth will not interfere with the measurement" - said one of the authors of the study, Prof. Robert Bogdanowicz from the Gdańsk University of Technology.

According to Bogdanowicz, proteins characteristic for each strain are found on the surface of pathogens. The company SensDx provided scientists with antibodies that capture these compounds. "The latest influenza vaccine only works on four strains of influenza virus, and all variants of the virus have such proteins on the surface that bind to the antibody" - said Prof. Bogdanowicz. If a protein encounters an antibody, the electrical parameters change and the sensor shows that an infection has occurred.

Such a high sensitivity of the device is possible due to the use of diamond surfaces to which antibodies or other macromolecules are attached. These surfaces are developed in the laboratory of the Center of Advanced Technologies "POMORZE". "We produce them in a diamond synthesis machine" - said Prof. Bogdanowicz. He noted that the diamond layers have a thickness of micrometers (a micrometer is a thousandth of a millimeter). He estimated that the solution would not be expensive, especially if the disposable tips would be returned to the manufacturer and processed for reuse.

"Imagine that in the clinic during the flu season, even before entering the waiting room, a nurse tests the patient with the sensor and immediately knows which waiting room to refer the patient to so that he or she does not infect other patients with the flu" - Prof. Bogdanowicz spoke about possible applications of the sensor.

Specialists from SensDx are also working on detecting many other types of diseases, not only infections (urological, intimate, respiratory infections), as well as cancers or abdominal aortic aneurysms. The platform developed jointly by scientists offers a wide range of possibilities and to create sensitive diagnostic tools that will detect disease changes at an early stage of their development.